drm/amdgpu: drop GB_GPU_ID from the golden settings

That register is marked deprecated, reading it results in a bus error.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>